Noise optimisation for the design of a reliable high speed X-ray readout integrated circuit

On the basis of the design of an X-ray readout integrated circuit, we present in this paper the noise analysis which has to be performed in order to implement a reliable system. In this context, we exploit the various noise sources originating both at the device and at the circuit level of the system. We present the crucial noise contributors, calculate the noise level and present optimisation methods to accommodate the best noise performance in readout circuits. The noise contribution of the input amplification stage to the overall system noise performance is treated in detail. The designer’s alternative choices regarding the input capacitance scaling (device level) and the feedback resistance (circuit level) are properly investigated. Other issues such as signal filtering and mixed signal design are also addressed.